"Your Sister's Sister" is as funny and complex as a real-life love story

I love Your Sister's Sister a lot. What is it about this tense, amusing, sexy film? I recall two scenes.

One is near the end. A character named Jack (Mark Duplass), who is a schlub, delivers a beautiful speech. Like the rest of the film, it's heartfelt and tinged with irony. It's hopeful and romantic, and it makes me think of Lloyd Dobler, the hopeful romantic played by John Cusack in Cameron Crowe's great 1989 film Say Anything.... The difference is that Lloyd is a teenage loser who has plenty of time to sort out his life. Jack is an older loser, and Duplass delivers his lines with the exhaustion you'd expect in an underachiever veering headlong toward middle age.

The other scene is earlier, and it sets up the basic conflict. Still grieving a year after his brother's death, Jack leaves Seattle for some quiet time at a nearby island getaway. It belongs to the family of his best friend, Iris (Emily Blunt). At the house, he's surprised to find Iris' sister Hannah (Rosemarie DeWitt). She's nursing a breakup, and before long the two begin drinking tequila together. What follows, awkwardly, is the sweetest, truest seduction scene I can recall.

The lines by writer-director Lynn Shelton (Humpday) are sharp and wry, and the sexual tension you'd expect is made complicated by a misunderstanding. Hannah's ex is a woman, and Jack assumes Hannah is a lesbian. He seems too preoccupied to really flirt with conviction, but in this case, sex apparently is not a possibility. That puts him at his ease. Sex does in fact follow, and it looks like real sex, clumsy and funny, not movie sex.

The next morning, Iris arrives unexpectedly. Jack and Hannah lie about what happened. Revelations follow, some of them shattering.

Your Sister's Sister belongs to a genre I like a lot. It's a small, smart, sad comedy, like the films Noah Baumbach makes. (Duplass appeared in Baumbach's Greenberg.) There's an ease to the performances, and Shelton's dialogue sounds natural, unforced. The screenplay takes on questions that aren't gigantic, philosophically speaking, but that people really do think about. Can men and women be close friends? How long is grief supposed to last? What do our family ties mean? How do we tell people we care about them?

Shelton ties up her loose ends perhaps too neatly. I sense wish fulfillment in the film's conclusion, including that marvelous speech by Duplass. I can live with this minor flaw, because I root for the characters. They're complicated. They make mistakes. They're driven by selfishness and caring and desire all at once. Like many people.